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[perl #36380] Re-order interpvar.h/embedvar.h to shrink the interpreter struct

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From:
James E Keenan via RT
Date:
May 26, 2012 18:26
Subject:
[perl #36380] Re-order interpvar.h/embedvar.h to shrink the interpreter struct
Message ID:
rt-3.6.HEAD-7788-1338081974-1852.36380-15-0@perl.org
On Tue Jul 05 10:59:49 2005, ni-s wrote:
> Nicholas Clark <perl5-porters@perl.org> writes:
> >
> >It would seem a good idea to re-order this and prune the odd unused
>    entries.
> >thrdvar.h has this comment:
> >
> >/* Important ones in the first cache line (if alignment is done
>    right) */
> >
> >so clearly some of the current ordering is important.
> 
> I agree with the idea of re-ordering.
> I suspect the comment was wishful thinking (on my part? - 'twas I
> that invented the xxxxvar.h).
> 
> The xxxvar.h stuff was to allow olde global variables and multiplicty
>    etc.
> via pointer to share source. I am (still) curious as to how much speed
> gain the global variables give us. Most RISCs (which can't do
> 32-bit immediate) will access a globals via a register anyway.
> So I think most gain will come on x86 where explicit pointer
> adds to register preasure...
> 
> >
> >Nicholas Clark
> >


Nicholas:  Should we still be considering the fix you suggested in this RT?

Thank you very much.
Jim Keenan

---
via perlbug:  queue: perl5 status: open
https://rt.perl.org:443/rt3/Ticket/Display.html?id=36380

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